The controlled expansion of gases forms the basis for the majority of non-electrical rotational engines in use today. These engines include reciprocating, rotary, and turbine engines, and may be driven by heat, such as with heat engines, or other forms of energy. Heat engines optionally use combustion, solar, geothermal, nuclear, and/or forms of thermal energy. Further, combustion-based heat engines optionally utilize either an internal or an external combustion system, which are further described infra.
Internal Combustion Engines
Internal combustion engines derive power from the combustion of a fuel within the engine itself. Typical internal combustion engines include reciprocating engines, rotary engines, and turbine engines.
Internal combustion reciprocating engines convert the expansion of burning gases, such as an air-fuel mixture, into the linear movement of pistons within cylinders. This linear movement is subsequently converted into rotational movement through connecting rods and a crankshaft. Examples of internal combustion reciprocating engines are the common automotive gasoline and diesel engines.
Internal combustion rotary engines use rotors and chambers to more directly convert the expansion of burning gases into rotational movement. An example of an internal combustion rotary engine is a Wankel engine, which utilizes a triangular rotor that revolves in a chamber, instead of pistons within cylinders. The Wankel engine has fewer moving parts and is generally smaller and lighter, for a given power output, than an equivalent internal combustion reciprocating engine.
Internal combustion turbine engines direct the expansion of burning gases against a turbine, which subsequently rotates. An example of an internal combustion turbine engine is a turboprop aircraft engine, in which the turbine is coupled to a propeller to provide motive power for the aircraft.
Internal combustion turbine engines are often used as thrust engines, where the expansion of the burning gases exit the engine in a controlled manner to produce thrust. An example of an internal combustion turbine/thrust engine is the turbofan aircraft engine, in which the rotation of the turbine is typically coupled back to a compressor, which increases the pressure of the air in the air-fuel mixture and increases the resultant thrust.
All internal combustion engines suffer from poor efficiency; only a small percentage of the potential energy is released during combustion as the combustion is invariably incomplete. Of energy released in combustion, only a small percentage is converted into rotational energy while the rest is dissipated as heat.
If the fuel used in an internal combustion engine is a typical hydrocarbon or hydrocarbon-based compound, such as gasoline, diesel oil, and/or jet fuel, then the partial combustion characteristic of internal combustion engines causes the release of a range of combustion by-products pollutants into the atmosphere via an engine exhaust. To reduce the quantity of pollutants, a support system including a catalytic converter and other apparatus is typically necessitated. Even with the support system, a significant quantity of pollutants are released into the atmosphere as a result of incomplete combustion when using an internal combustion engine.
Because internal combustion engines depend upon the rapid and explosive combustion of fuel within the engine itself, the engine must be engineered to withstand a considerable amount of heat and pressure. These are drawbacks that require a more robust and more complex engine over external combustion engines of similar power output.
External Combustion Engines
External combustion engines derive power from the combustion of a fuel in a combustion chamber separate from the engine. A Rankine-cycle engine typifies a modern external combustion engine. In a Rankine-cycle engine, fuel is burned in the combustion chamber and used to heat a liquid at substantially constant pressure. The liquid is vaporized to a gas, which is passed into the engine where it expands. The desired rotational energy and/or power is derived from the expansion energy of the gas. Typical external combustion engines also include reciprocating engines, rotary engines, and turbine engines, described infra.
External combustion reciprocating engines convert the expansion of heated gases into the linear movement of pistons within cylinders and the linear movement is subsequently converted into rotational movement through linkages. A conventional steam locomotive engine is used to illustrate functionality of an external combustion open-loop Rankine-cycle reciprocating engine. Fuel, such as wood, coal, or oil, is burned in a combustion chamber or firebox of the locomotive and is used to heat water at a substantially constant pressure. The water is vaporized to a gas or steam form and is passed into the cylinders. The expansion of the gas in the cylinders drives the pistons. Linkages or drive rods transform the piston movement into rotary power that is coupled to the wheels of the locomotive and is used to propel the locomotive down the track. The expanded gas is released into the atmosphere in the form of steam.
External combustion rotary engines use rotors and chambers instead of pistons, cylinders, and linkages to more directly convert the expansion of heated gases into rotational movement.
External combustion turbine engines direct the expansion of heated gases against a turbine, which then rotates. A modern nuclear power plant is an example of an external-combustion closed-loop Rankine-cycle turbine engine. Nuclear fuel is consumed in a combustion chamber known as a reactor and the resultant energy release is used to heat water. The water is vaporized to a gas, such as steam, which is directed against a turbine forcing rotation. The rotation of the turbine drives a generator to produce electricity. The expanded steam is then condensed back into water and is typically made available for reheating.
With proper design, external combustion engines are more efficient than corresponding internal combustion engines. Through the use of a combustion chamber, the fuel is more thoroughly consumed, releasing a greater percentage of the potential energy. Further, more thorough consumption means fewer combustion by-products and a corresponding reduction in pollutants.
Because external combustion engines do not themselves encompass the combustion of fuel, they are optionally engineered to operate at a lower pressure and a lower temperature than comparable internal combustion engines, which allows the use of less complex support systems, such as cooling and exhaust systems. The result is external combustion engines that are simpler and lighter for a given power output compared with internal combustion engines.
External Combustion Engine Types
Turbine Engines
Typical turbine engines operate at high rotational speeds. The high rotational speeds present several engineering challenges that typically result in specialized designs and materials, which adds to system complexity and cost. Further, to operate at low-to-moderate rotational speeds, turbine engines typically utilize a step-down transmission of some sort, which again adds to system complexity and cost.
Reciprocating Engines
Similarly, reciprocating engines require linkages to convert linear motion to rotary motion resulting in complex designs with many moving parts. In addition, the linear motion of the pistons and the motions of the linkages produce significant vibration, which results in a loss of efficiency and a decrease in engine life. To compensate, components are typically counterbalanced to reduce vibration, which again increases both design complexity and cost.
Heat Engines
Typical heat engines depend upon the diabatic expansion of the gas. That is, as the gas expands, it loses heat. This diabatic expansion represents a loss of energy.
Patents and patent applications related to the current invention are summarized here.
Rotary Engine Types
    J. Faucett, “Improvement in Rotary Engines”, U.S. Pat. No. 122,713 (Jan. 16, 1872) describes a class of rotary steam engines using a revolving disk instead of a piston. Particularly, the engine uses a pair of oval concentrics secured to a single transverse shaft, each revolving within a separated steam chamber.    R. Hoffman, “Rotary Steam Engine”, U.S. Pat. No. 4,047,856 (Sep. 13, 1977) describes a unidirectional rotary steam power unit using a power fluid supplied through a hollow rotor and is conducted to working chambers using passages in walls of the housing controlled by seal means carried by the rotor.    D. Larson, “Rotary Internal Combustion Engine”, U.S. Pat. No. 4,178,900 (Dec. 18, 1979) describes a rotary internal combustion engine configured with a stator and two pairs of sockets. Wedges are affixed to each socket. Rotation of an inner rotor, the sides of the rotor defining a cam, allows pivoting of the wedges, which alters chamber sizes between the rotor and the stator.    J. Ramer, “Method for Operating a Rotary Engine”, U.S. Pat. No. 4,203,410 (May 20, 1980) describes a rotary engine having a pair of spaced coaxial rotors in a housing, each rotor rotating separate rotor chambers. An axially extending chamber in the housing communicates the rotor chambers.    F. Lowther, “Vehicle Braking and Kinetic Energy Recovery System”, U.S. Pat. No. 4,290,268 (Sep. 22, 1981) describes an auxiliary kinetic energy recovery system incorporating a rotary sliding vane engine and/or compressor, using compressed air or electrical energy recovered from the kinetic energy of the braking system, with controls including the regulation of the inlet aperture.    O. Rosaen, “Rotary Engine”, U.S. Pat. No. 4,353,337 (Oct. 12, 1982) describes a rotary internal combustion engine having an elliptically formed internal chamber, with a plurality of vane members slidably disposed within the rotor, constructed to ensure a sealing engagement between the vane member and the wall surface.    J. Herrero, et. al., “Rotary Electrohydraulic Device With Axially Sliding Vanes”, U.S. Pat. No. 4,492,541 (Jan. 8, 1985) describes a rotary electrohydraulic device applicable as braking or slackening device.    O. Lien, “Rotary Engine”, U.S. Pat. No. 4,721,079 (Jan. 26, 1988) describes a rotary engine configured with rotors, forming opposite sides of the combustion chambers, rotated on an angled, non-rotatable shaft through which a straight power shaft passes.    K. Yang, “Rotary Engine”, U.S. Pat. No. 4,813,388 (Mar. 21, 1989) describes an engine having a pair of cylindrical hubs interleaved in a mesh type rotary engine, each of the cylindrical hubs defining combustion and expansion chambers.    A. Nardi, “Rotary Expander”, U.S. Pat. No. 5,039,290 (Aug. 13, 1991) describes a positive displacement single expansion steam engine having cylinder heads fixed to a wall of the engine, a rotatable power shaft having a plurality of nests, and a free-floating piston in each nest.    G. Testea, et. al., “Rotary Engine System”, U.S. Pat. No. 5,235,945 (Aug. 17, 1993) describes an internal combustion rotary engine having an offset rotor for rotation about an axis eccentric to a central axis of a cylindrical cavity that provides the working chambers of the engine.    R. Weatherston, “Two Rotor Sliding Vane Compressor”, U.S. Pat. No. 5,681,153 (Oct. 28, 1997) describes a two-rotor sliding member rotary compressor including an inner rotor, an outer rotor eccentric to the inner rotor, and at least three sliding members between the inner rotor and the outer rotor.    G. Round, et. al., “Rotary Engine and Method of Operation”, U.S. Pat. No. 5,720,251 (Feb. 24, 1998) describes a rotary engine having an inner rotor and an outer rotor with the outer rotor being offset from the inner rotor. The outer rotor is configured with inward projecting lobes forming seals with outward extending radial arms of the inner rotor, the lobes and arms forming chambers of the engine.    J. Klassen, “Rotary Positive Displacement Engine”, U.S. Pat. No. 5,755,196 (May 26, 1998) describes an engine having a pair of rotors both housed within a single housing, where each rotor is mounted on an axis extending through a center of the housing, where the rotors interlock with each other to define chambers, where a contact face of a first rotor is defined by rotation of a conical section of a second rotor of the two rotors, such that there is a constant linear contact between opposing vanes on the two rotors.    M. Ichieda, “Side Pressure Type Rotary Engine”, U.S. Pat. No. 5,794,583 (Aug. 18, 1998) describes a side pressure type rotary engine configured with a suction port and an exhaust port. A suction blocking element and exhaust blocking element are timed for movement and use in synchronization with rotor rotation to convert expansive forces into a rotational force.    R. Saint-Hilaire, et al. “Quasiturbine Zero Vibration-Continuous Combustion Rotary Engine Compressor or Pump”, U.S. Pat. No. 6,164,263 (Dec. 26, 2000) describe a rotary engine using four degrees of freedom, where an assembly of four carriages supporting pivots of four pivoting blades forms a variable shape rotor.    J. Pelleja, “Rotary Internal Combustion Engine and Rotary Internal Combustion Engine Cycle”, U.S. Pat. No. 6,247,443 B1 (Jun. 19, 2001) describes an internal combustion rotary engine configured with a set of push rod vanes arranged in a staggered and radial arrangement relative to a drive shaft of the engine.    R. Pekau, “Variable Geometry Toroidal Engine”, U.S. Pat. No. 6,546,908 B1 (Apr. 15, 2003) describes a rotary engine including a single toroidal cylinder and a set of pistons on a rotating circular piston assembly where the pistons are mechanically extendable and retractable in synchronization with opening and closing of a disk valve.    M. King, “Variable Vane Rotary Engine”, U.S. Pat. No. 6,729,296 B2 (May 4, 2004) describes a rotary engine including: (1) a concentric stator sandwiched between a front wall and an aft wall enclosing a cylindrical inner space and (2) a network of combustors stationed about the periphery of the stator.    O. Al-Hawaj, “Supercharged Radial Vane Rotary Device”, U.S. Pat. No. 6,772,728 B2 (Aug. 10, 2004) describes two and four phase internal combustion engines having a donut shaped rotor assembly with an integrated axial pump portion, incorporating cam followers.    M. Kight, “Bimodal Fan, Heat Exchanger and Bypass Air Supercharging for Piston or Rotary Driven Turbine”, U.S. Pat. No. 6,786,036 B2 (Sep. 7, 2004) describes a turbine for aircraft use where the turbine includes a heat exchanger with minimal drag for increasing the engine effectiveness through an enthalpy increase on the working fluid.    S. Wang, “Rotary Engine with Vanes Rotatable by Compressed Gas Injected Thereon”, U.S. Pat. No. 7,845,332 B2 (Dec. 7, 2010) describes a planetary gear rotary engine for internal combustion, where a rotor rotates within an outer shell. With a given rotation of the rotor, vanes drive a power generating unit.Ignition    E. Pangman, “Multiple Vane Rotary Internal Combustion Engine”, U.S. Pat. No. 5,277,158 (Jan. 11, 1994) describes a rotary engine having a fuel ignition system provided to more than one combustion chamber at a time by expanding gases passing through a plasma bleed-over groove. Further exhaust gases are removed by a secondary system using a venturi creating negative pressure.Rotors    Y. Ishizuka, et. al., “Sliding Vane Compressor with End Face Inserts or Rotor”, U.S. Pat. No. 4,242,065 (Dec. 30, 1980) describes a sliding vane compressor having a rotor, the rotor having axially endfaces, which are juxtaposed. The axial rotor endfaces having a material of higher thermal coefficient of expansion than a material of the rotor itself, the thermal expansion of the endfaces used to set a spacing.    T. Edwards, “Non-Contact Rotary Vane Gas Expanding Apparatus”, U.S. Pat. No. 5,501,586 (Mar. 26, 1991) describes a non-contact rotary vane gas expanding apparatus having a stator housing, a rotor, a plurality of vanes in radial slots of the rotor, a plurality of gas receiving pockets in the rotor adjacent to the radial slots of the rotor, and formations in the stator housing to effectuate transfer of gas under pressure through the stator housing to the gas receiving pockets.    J. Minier, “Rotary Internal Combustion Engine”, U.S. Pat. No. 6,070,565 (Jun. 6, 2000) describes an internal combustion engine apparatus containing a slotted yoke positioned for controlling the sliding of the vane blades.Vanes    R. Jenkins, et. al., “Rotary Engine”, U.S. Pat. No. 4,064,841 (Dec. 27, 1977) describes a rotary engine having a stator, an offset, a track in the rotor, and roller vanes running in the track, where each vane extends outward to separate the rotor/stator gap into chambers.    R. Roberts, et. al., “Rotary Sliding Vane Compressor with Magnetic Vane Retractor”, U.S. Pat. No. 4,132,512 (Jan. 2, 1979) describes a rotary sliding vane compressor having magnetic vane retractor means to control the pumping capacity of the compressor without the use of an on/off clutch in the drive system.    D. August, “Rotary Energy-Transmitting Mechanism”, U.S. Pat. No. 4,191,032 (Mar. 4, 1980) describes a rotary energy-transmitting device configure with a stator, an inner rotor and vanes separating the stator and rotor into chambers, where the vanes each pivot on a rolling ball mechanism, the ball mechanisms substantially embedded in the rotor.    J. Taylor, “Rotary Internal Combustion Engine”, U.S. Pat. No. 4,515,123 (May 7, 1985) describes a rotary internal combustion engine which provides spring-loaded vanes seated opposed within a cylindrical cavity in which a rotary transfer valve rotates on a shaft.    S. Sumikawa, et al. “Sliding-vane Rotary Compressor for Automotive Air Conditioner”, U.S. Pat. No. 4,580,950 (Apr. 8, 1986) describe a sliding-vane rotary compressor utilizing a control valve constructed to actuate in immediate response to a change in pressure of a fluid to be compressed able to reduce the flow of the fluid when the engine rate is high.    W. Crittenden, “Rotary Internal Combustion engine”, U.S. Pat. No. 4,638,776 (Jan. 27, 1987) describes a rotary internal combustion engine utilizing a radial sliding vane on an inner surface of an eccentric circular chamber, and an arcuate transfer passage communicating between the chambers via slots in the rotors adjacent the vanes.    R. Wilks, “Rotary Piston Engine”, U.S. Pat. No. 4,817,567 (Apr. 4, 1989) describes a rotary piston engine having a pear-shaped piston, with a piston vane, and four spring-loaded vanes mounted for reciprocal movement.    K. Pie, “Rotary Device with Vanes Composed of Vane Segments”, U.S. Pat. No. 5,224,850 (Jul. 6, 1993) describes a rotary engine having multipart vanes between an inner rotor and an outer housing, where each vane has end parts and an intermediate part. In a first embodiment, the intermediate part and end part have cooperating inclined ramp faces, such that an outwardly directed force applied to the vane or by a biasing spring causes the end parts to thrust laterally via a wedging action. In a second embodiment, the end parts and intermediate part are separated by wedging members, located in the intermediate portion, acting on the end parts.    S. Anderson, “Gas Compressor/Expander”, U.S. Pat. No. 5,379,736 (Jan. 10, 1995) describes an air compressor and gas expander having an inner rotor, an outer stator, and a set of vanes, where each vanes independently rotates, along an axis parallel to an axis of rotation of the rotor, to separate a space between the rotor and stator into chambers.    B. Mallen, et. al., “Sliding Vane Engine”, U.S. Pat. No. 5,524,587 (Jun. 11, 1996) describes a sliding vane engine including: a stator and a rotor in relative rotation and vanes containing pins that extend into a pin channel for controlling sliding motion of the vanes.    J. Penn, “Radial Vane Rotary Engine”, U.S. Pat. No. 5,540,199 (Jul. 30, 1996) describes a radial vane rotary engine having an inner space with a substantially constant distance between an inner cam and an outer stator, where a set of fixed length vanes separate the inner space into chambers. The inner rotating cam forces movement of each vane to contact the outer stator during each engine cycle.    L. Hedelin, “Sliding Vane Machine Having Vane Guides and Inlet Opening Regulation”, U.S. Pat. No. 5,558,511 (Sep. 24, 1996) describes a sliding vane machine with a cylindrical rotor placed in a housing, the rotor being rotatably mounted in the housing at one point and being provided with a number of vanes, where movement of the vanes is guided along a guide race in the housing.    K. Kirtley, et. al., “Rotary Vane Pump With Continuous Carbon Fiber Reinforced PolyEtherEtherKetone (PEEK) Vanes”, U.S. Pat. No. 6,364,646 B1 (Apr. 2, 2002) describes a rotary paddle pump with sliding vanes and a stationary side wall, where the vanes and side wall are fabricated using a continuous carbon-fiber reinforced polyetheretherketone material, having self-lubrication properties.    R. Davidow, “Steam-Powered Rotary Engine”, U.S. Pat. No. 6,565,310 B1 (May 20, 2003) describes a steam-powered rotary engine having a rotor arm assembly and an outer ring, where steam ejected from an outer end of the rotor arm assembly impacts at essentially right angle onto steps in the outer ring causing the rotor arm to rotate in a direction opposite the direction of travel of the exiting steam.    D. Renegar, “Flexible Vane Rotary Engine”, U.S. Pat. No. 6,659,065 B1 (Dec. 9, 2003) describes an internal combustion rotary engine comprising a rotor spinning in an oval cavity and flexible vanes, defining four chambers, that bend in response to cyclical variation in distance between the rotor and an inner wall of a housing of the rotary engine.    R. Saint-Hilaire, et. al., “Quasiturbine (Qurbine) Rotor with Central Annular Support and Ventilation”, U.S. Pat. No. 6,899,075 B2 (May 31, 2005) describe a quasiturbine having a rotor arrangement peripherally supported by four rolling carriages, the carriages taking the pressure load of pivoting blades forming the rotor and transferring the load to the opposite internal contoured housing wall. The pivoting blades each include wheel bearing rolling on annular tracks attached to the central area of the lateral side covers forming part of the stator casing.    T. Hamada, et al. “Sliding Structure for Automotive Engine”, U.S. Pat. No. 7,255,083 (Aug. 14, 2007) describe an automotive engine having a sliding portion, such as a rotary vane, where the sliding portion has a hard carbon film formed on the base of the sliding portion.    S. MacMurray, “Single Cycle Elliptical Rotary Engine”, U.S. Pat. No. 7,395,805 B1 (Jul. 8, 2008) describes a rotary engine configured a rotor housing having a bisected, offset elliptical interior wall a rotor member disposed therein. Four vanes rotate with the rotor. The rotor vanes are forced out by a pressurized oxygen/fuel mixture entering behind the vanes through ports and the vanes are pushed back into the rotor due to narrowing elliptical walls of the housing.    W. Peitzke, et. al., “Multilobe Rotary Motion Asymmetric Compression/Expansion Engine”, U.S. Pat. No. 7,578,278 B2 (Aug. 25, 2009) describe a rotary engine with multiple pivotally mounted lobes desmodromically extendible and retractable from a rotor to trace asymmetric volumes for inlet and compression and for inlet and exhaust based on the contour of the engine case, which the lobes sealingly engage.    J. Rodgers, “Rotary Engine”, U.S. Pat. No. 7,713,042, B1 (May 11, 2010) describes a rotary engine configured to use compressed air or high pressure steam to produce power. The engine includes a rotor having three slotted piston, opposed inlet ports running through a central valve into the slotted pistons, and a casing having two exhaust ports.Valves    T. Larson, “Rotary Engine”, U.S. Pat. No. 4,548,171 (Oct. 22, 1985) describes a rotary engine having a plurality of passages for intake, compression, expansion, and exhaust and valve means to selectively open and close the passages in a cycle of the engine.    S. Nagata, et. al., “Four Cycle Rotary Engine”, U.S. Pat. No. 5,937,820 (Aug. 17, 1999) describes a rotary engine configured with an oblong casing, a circular shaped rotor therein, vanes attached to the rotor, and inlet and outlet valves. Means for manipulating the inlet and outlet valves are housed in the rotor.Seals    J. Wyman, “Rotary Motor”, U.S. Pat. No. 4,115,045 (Sep. 19, 1978) describes a rotary steam engine having a peripheral, circular casing with side walls defining an interior cylindrical section and a rotor adapted to rotate therein, where the rotor includes a series of spaced transverse lobes with spring-biased transverse seals adapted to engage the inner periphery of the casing and the casing having a series of spaced spring-biased transverse vanes adapted to engage the outer periphery seals and lobes of the rotor.    H. Banasiuk, “Floating Seal System for Rotary Devices”, U.S. Pat. No. 4,399,863 (Aug. 23, 1983) describes a floating seal system for rotary devices to reduce gas leakage around the rotary device. The peripheral seal bodies have a generally U-shaped cross-section with one of the legs secured to a support member and the other forms a contacting seal against the rotary device. A resilient flexible tube is positioned within a tubular channel to reduce gas leakage across the tubular channel and a spacer extends beyond the face of the floating channel to provide a desired clearance between the floating channel and the face of the rotary device.    C. David, “External Combustion Rotary Engine”, U.S. Pat. No. 4,760,701 (Aug. 2, 1988) describes an external combustion rotary engine configured to operate using compressed air in internal expansion chambers. A fraction of the compressed air is further compressed and used as an air pad cushion to isolate rotating engine components from fixed position engine components.    E. Slaughter, “Hinged Valved Rotary Engine with Separate Compression and Expansion Chambers”, U.S. Pat. No. 4,860,704 (Aug. 29, 1989) describes a hinge valved rotary engine where air is compressed by cooperation of a hinged compression valve that sealingly engages a compression rotor of the engine. Further, vanes expansion rotor lobe seals are forced into contact with the peripheral surface of the expansion chamber using springs.    C. Parme, “Seal Rings for the Roller on a Rotary Compressor”, U.S. Pat. No. 5,116,208 (May 26, 1992) describes a sliding vane rotary pump, including: a housing, a roller mounted in the cylindrical housing, and bearing plates for closing top and bottom ends of the cylindrical opening. A seal ring is disposed within a counterbored surface of each end of the cylindrical ring, the internal space is filled with a pressurized fluid supplied by the compressor, and the pressurized fluid exerts a bias force on the seal rings causing the seal rings to move outwardly from the ends of the roller to form a seal with the bearing plates.    J. Kolhouse, “Self-Sealing Water Pump Seal”, U.S. Pat. No. 5,336,047 (Aug. 9, 1994) describes a self-sealing water pump seal having a barrier after a primary seal, the barrier designed to become clogged over time with solids leaking past the primary seal, thereby forming a secondary seal.    O. Lien, “Rotary Engine Piston and Seal Assembly”, U.S. Pat. No. 5,419,691 (May 30, 1995) describes a rotary engine piston and seal assembly having a cube shaped piston and a pair of grooves running around all four sliding side surfaces of the piston. the grooves contain a series of segmented metal seal compressed against mating surfaces with seal springs.    T. Stoll, et. al., “Hinged Vane Rotary Pump”, U.S. Pat. No. 5,571,005 (Nov. 5, 1996) describes a hinged vane rotary pump including: a cylindrical chamber, a rotor eccentrically mounted within the chamber, and a plurality hinged vanes, where wear on the vane effectively moves to the center of the vane.    D. Andres, “Air Bearing Rotary Engine”, U.S. Pat. No. 5,571,244 (Nov. 5, 1996) describes a rotary engine including vanes having tip apertures supplied with pressurized fluid to provide air bearings between the vane tip and a casing of the stator housing.    J. Klassen, “Rotary Positive Displacement Engine”, U.S. Pat. No. 6,036,463 (Mar. 14, 2000) describes an engine having a pair of rotors both housed within a single housing, where each rotor is mounted on an axis extending through a center of the housing, where the rotors interlock with each other to define chambers, where a contact face of a first rotor is defined by rotation of a conical section of a second rotor of the two rotors, such that there is a constant linear contact between opposing vanes on the two rotors.    J. Klassen, “Rotary Engine and Method for Determining Engagement Surface Contours Therefor”, U.S. Pat. No. 6,739,852 B1 (May 25, 2004) describes a rotary engine configured with rotor surfaces that are mirror images of engine interior contours to form a seal and recesses for interrupting the seal at predetermined points in a rotational cycle of the engine.    B. Garcia, “Rotary Internal Combustion Engine”, U.S. patent application no. 2006/0102139 A1 (May 18, 2006) describes a rotary internal combustion engine having a coaxial stator, a rotor, and a transmission system, where the transmission system causes retraction movements of a first group of blades to transmit to a second group of blades forming a seal between the free edge of the blades and the inner surface of the engine.Exhaust    W. Doerner, et. al., “Rotary Rankine Engine Powered Electric Generating Apparatus”, U.S. Pat. No. 3,950,950 (Apr. 20, 1976) describe a rotary closed Rankine cycle turbine engine powered electric generating apparatus having a single condenser and/or a primary and secondary condenser for condensing exhaust vapors.    D. Aden, et. al., “Sliding Vane Pump”, U.S. Pat. No. 6,497,557 B2 (Dec. 24, 2002) describes a sliding vane pump having a plurality of inlet ports, internal discharge ports, and at least two discharge ports where all of the fluid from one of the internal discharge ports exits through one of the external discharge ports.    J. Klassen, “Method for Determining Engagement Surface Contours for a Rotor of an Engine”, U.S. Pat. No. 6,634,873 B2 (Oct. 21, 2003) describes a rotary engine configured with rotor surfaces that are mirror images of engine interior contours to form a seal and recesses for interrupting the seal at predetermined points in a rotational cycle of the engine.    D. Patterson, et. al., “Combustion and Exhaust Heads for Fluid Turbine Engines”, U.S. Pat. No. 6,799,549 B1 (Oct. 5, 2004) describes an internal combustion rotary turbine engine including controls for opening and closing an exhaust valve during engine operation.    R. Gorski, “Gorski Rotary Engine”, U.S. Pat. No. 7,073,477 B2 (Jul. 11, 2006) describes a rotary engine configured with solid vanes extending from a rotor to an interior wall of the stator housing. A series of grooves in the interior wall permit the expanding exhaust gases to by-pass the vanes proximate the combustion chamber to engage the larger surface area of the vane protruding from the rotor.    H. Maeng, “Sliding Vane of Rotors”, U.S. Pat. No. 7,674,101 B2 (Mar. 9, 2010) describes a sliding vane extending through a rotor in diametrically opposed directions and rotating with the rotor. Diametrically opposed ends of the sliding vane include sealing slots. The sliding vane further includes two pairs of compression plates provided in plate sealing slots for sealing the edges of the vane, the compression plates activated using springs in the vane.    E. Carnahan, “External Heat Engine of the Rotary Vane Type and Compressor/Expander”, U.S. patent application no. US 2008/0041056 A1 (Feb. 21, 2008) describes a rotary engine using injected cool liquid into a compression section of the engine.Cooling    T. Maruyama, et al. “Rotary Vane Compressor With Suction Port Adjustment”, U.S. Pat. No. 4,486,158 (Dec. 4, 1984) describe a sliding vane type rotary compressor with suction port adjustment, of which refrigerating capacity at the high speed operation is suppressed by making use of suction loss involved when refrigerant pressure in the vane chamber becomes lower than the pressure of the refrigerant supply source in the suction stroke of the compressor.    R. Ullyott, “Internal Cooling System for Rotary Engine”, U.S. Pat. No. 7,412,831 B2 (Aug. 19, 2008) describes a rotary combustion engine with self-cooling system, where the cooling system includes: a heat exchanging interface and a drive fan integrated on an output shaft of the rotary engine, the fan providing a flow of forced air over the heat exchanging interface.Varying Loads    T. Alund, “Sliding Vane Machines”, U.S. Pat. No. 4,046,493 (Sep. 6, 1977) describes a sliding vane machine using a valve and pressure plates to control the working area of valves in the sliding vane machine.Jet    A. Schlote, “Rotary Heat Engine”, U.S. Pat. No. 5,408,824 (Apr. 25, 1995) describes a jet-propelled rotary engine having a rotor rotating about an axis and at least one jet assembly secured to the rotor and adapted for combustion of a pressurized oxygen-fuel mixture.Problem Statement
What is needed is an engine, pump, expander, and/or compressor that more efficiently converts fuel or energy into motion, work, power, stored energy, and/or force. For example, what is needed is an external combustion rotary heat engine that more efficiently converts about adiabatic expansive energy of the gases driving the engine into rotational power and/or energy for use driving a variety of applications.